Process for cleaning railway rail and improving the traction

ABSTRACT

In a process for cleaning the rails and improving the traction of a locomotive wheel on a railroad rail, a substance normally solid, friable and abrasive is heated to the molten state and deposited as a coat on the wheel-contacting surface of the rail, whereupon it immediately solidifies, vaporizing some contaminants and incorporating others. The solidified coat of the substance is crushed by the locomotive wheel, and the crushed substance scours the rail and improves traction between the rail and the wheel.

Umted States Patent 1191 1111 3,850,691 Bleil et al. Nov. 26, 1974 15 1 PROCESS FOR CLEANING RAILWAY RAIL 1,423,429 7/1922 Johns 291/20 AND IMPROVING THE TRACTION 146261285 4/1927 2,597,719 5/1952 [75] Inventors: Carl E. Bleil, B1rmingham; Fay E. 2 319,631 6/1958 Gifford, Lathrup Village, both of 2,824,526 2/1958 Mich. 2,877,716 3/1959 2,890,970 6/1959 1 Asslgneeg $93? Corporation 3,621,179 11/1971 Tylko 104/279 e r01, 1c

[22] Filed: Apr. 26, 1973 Primary ExaminerM. Henson Wood, Jr.

Assistant Examiner-Howard Beltran U App! 354473 Attorney, Agent, or Firm-Pau1 Fitzpatrick [52] US. Cl 134/4, 51/178,51/28111, 57 ABSTRACT 104/] R, 104/279, 117/8, 1l7/93.1 PF, 117/129 118M053, 18/1 I8, 291/], 291/3 In a process for clean ng the ralls and improvmg the 291/19, 291/20 tract1on of a locomotive wheel'on a rallroad rail, 21 [51] Int CL Bosh U04 Bosh 7/02 861C 15/10 Substance normally solid, friable and abrasive is [58] Field of m4 279 heated to the molten state and deposited as a coat on 1 17/491 291/! g the wheel-contacting surface of the rail, whereupon it 2O 5 50178 ZSIR immediately solidifies, vaporizing some contaminants and incorporating others. The solidified coat of the substance 1s crushed by the locomotive wheel, and the [56] References Cited crushed substance scours the rai11 and improves trac- UNITED STATES PATENTS tion between the rail and the wheel. 976,627 11/1910 Boynton 118/9 1 4 Claims, 2 Drawing Figures Pmmm w w 3.850.691

GAS

SUPPLY PROCESS FOR CLEANING RAILWAY RAIL AND IMPROVING THE TRACTION BACKGROUND OF THE INVENTION One of the fundamental parameters that determines the performance of locomotives is the traction between the locomotive wheel and the rail. Thin layers of or ganic contaminants, principally oil originating from wheel journals and rail switches, are continuously deposited upon railroad rails. These layers act as lubricants and seriously degrade the traction between the wheel and the rail.

In the past, the principal means of improving rail traction has been to spray sand on the rail directly in front of the locomotive wheel. This process has been somewhat successful in improving traction; however, it

has a number of disadvantages which have caused a Other methods of improving rail traction have been tried, but little improvement has resulted. Attempts have been made to chemically clean the rails; however, cleaning with alkalies and acid has proved incomplete and inconsistent, and cleaning with detergents is prohibitively expensive. Chemical rail conditioners have resulted in only marginal improvement. The use of a high-energy spark discharge between a locomotive mounted probe and the rail to volatilize rail contaminates has proved effective in increasing traction but has its own serious disadvantages, such as the high energy required, unacceptably small spacing required between the probe and the rail, severe rail deterioration and electrical noise.

A recently suggested process, the treatment of rails by a plasma torch, has proved effective in increasing rail traction, but still has serious problems. As described by co-inventor Gifford and R. T. Yoshino in Plasma Treatment of Railway Rails to Improve Traction, American Society of Mechanical Engineers Paper No. 70-WA/RR-l (1970), the process requires excessive power, close spacing of the torch from the rail, and additional safety and maintenance problems.-

SUMMARY OF THE INVENTION The process of this invention effectively improves the traction of railroad rails while avoiding or reducing in seriousness the problems of the prior art processes. A substance which is solid, friable and abrasive in the ambient temperature range of railroad rails is heated to its molten state and deposited on the top surface of the rail immediately in front of a locomotive drive wheel. The substance can be stored in a powdered form and both heated and deposited by means of a plasma torch or can be maintained in a molten state and sprayed on to the track by high pressure gas. The parameters of the process are chosen so that the substance arrives at the surface of the rail in the molten statebut immediately solidifies upon contact with the rail. In the process of solidification, a portion of the rail contaminants is va porized and another portion is incorporated in the solid coat of the substance. As the locomotive wheel rolls over the coated rail, the substance is crushed into an abrasive powder which simultaneously scours the rail to remove any remaining contaminants and makes its own contribution to increased traction.

Further details and advantages of the invention will be apparent from the following drawings and detailed description of the preferred embodiments.

SUMMARY OF THE DRAWINGS FIG. 1 is a schematic drawing of one embodiment of this invention.

FIG. 2 is a schematic drawing of another embodiment of this invention.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to the figures, a driving wheel 2 of a locomotive rolls on the wheel-contacting surface 3 of a railroad rail 4 in the direction indicated by the arrow. Coating apparatus, generally indicated as 6 in FIG. 1 and 7 in FIG. 2, is carried on the locomotive and deposits a coating of a selected substance on the wheel contacting surface 3 of the rail 4 immediately in front of the wheel 2 in the direction of its movement.

The selected substance must have a number of properties. The substance must be a solid at all naturally found ambient rail temperatures. The solid substance must be friable, so that it will be crushed to a powder by the wheel 2 under the weight of the locomotive. The substance should also be abrasive so that it will scour the surface 3 of the rail under the wheel 2 and so that it will itself serve as an intermediate substance to increase the coefiicient of friction between the wheel 2 and the rail 4. On the other hand, the abrasiveness should not be so great as to cause unacceptably accelerated wear of the rail 4 and wheel 2.

The substance, solid at ambient temperatures, should have a melting point high enough that the molten substance is able to vaporize at least some of the oil or other contaminants on the rail. 4 upon contact; however, the temperature of the molten substance must not be so high that the molten substance cannot be safely and reliably handled with present day equipment. In addition, the molten substance must wet and adhere to steel at ambient temperatures sufficiently so that it will form a coating on the rail. Finally, the substance should be easily obtainable and inexpensive and should not itself degrade the environment around the railroad rail in the quantities necessary.

Examples of substances that possess these properties are glass, sand and slag. Each of these materials has been tested by being sprayed in a molten state onto a railroad rail and has been found to form a satisfactory coating on the rail. Each of these materials is readily available and inexpensive. Sand is already used by railroads, as previously mentioned, for increasing traction by a different process; and the amount used in this process would be much smaller. Slag is a commercially available byproduct of the reduction of iron and other metals from their ores and has long been used by railroads in some areas as ballast in the roadbeds. The choice of which material to use depends on many factors, some of which are controlled by the choice of coating apparatus. Although many examples could be shown for coating apparatus to be used in this process,

two such examples are given, one for each of the two embodiments of the process shown in FIGS. 1 and 2.

FIG. 1 shows the process wherein the substance is stored in the locomotive as a powder at ambient temperature and applied to the rail by a plasma torch 10. The plasma torch has a back electrode 11 and a ring shaped front electrode 12 separated by a cylindrical insulator 14, the front electrode 12 being connected to one side of a DC power source 16 and the back electrode 11 being connected to the opposite side of the DC power source 16 through a switch 18. A supply 20 of gas under pressure, the gas comprising a selected mixture of gases such as hydrogen, nitrogen or argon, which are commonly used in plasma torches, is con nected with the plasma torch 10 through a valve 22 and a conduit 24. The valve 22 is normally closed and is opened by an electromagnet 26 connected to a DC power source 28 through a switch 30, ganged to the switch 18 for co-movement therewith, when the switch 30 is closed.

In this embodiment, the substance is crushed or otherwise formed into a powder and stored on the locomotive in a hopper 32. When closed, switches 18 and 30 simultaneously activate the plasma torch I0 and open the valve 22 to allow gas to flow under pressure from the supply 20'to the conduit 24. The gas in conduit 24 aspirates the substance out of the hopper 32 and carries it into the plasma torch 10. The high heat of the plasma torch l0 melts the substance and the melted substance is sprayed onto the top surface 3 of the rail 4.

In another embodiment of the invention, shown in FIG. 2, the material is loaded into a heating container carried on the locomotive and shown in FIG. 2 to be surrounded by heating coils 42. The coils 42 supply sufficient heat to maintain the material in a molten state, for example, at 1500 C. A supply 44 of a gas under pressure such as compressed air is in communication with a sprayer 46 by means of a valve 48 and a conduit 50. The valve 48 is normally closed but is openable by an electromagnet 52 which is connectible to a DC power source 54 through a switch 56. The sprayer 46 contains a narrowed venturi area 58 which is in communication with the interior of the heating container 40 through a feeder tube 60. When the switch 56 is closed, gas under pressure flows from the supply 44 through the sprayer 46, where it aspirates molten substance from the heating container 40, and sprays the molten substance onto the surface 3 of the rail 4.

Regardless of the methods used to store, melt and spray the substance, from the point at which the substance is sprayed onto the surface 3 of the rail 4 all embodiments of the process are identical. As the molten substance hits the wheel contacting surface 3 of the rail 4, it forms a coat thereon and immediately cools and solidifies. Some of the heat given up by the substance in cooling serves to evaporate a portion of the organic contaminants on the rail 4. Another portion of the contaminants is trapped and incorporated in the coat as it solidifies. As the locomotive advances along the rail 4, the wheel 2 crushes the coat of solidified substance into an abrasive powder which scours the surface 3 clean. In addition, the powder itself, through its abrasiveness, tends to increase effective friction between the wheel 2 and the wheel contacting surface 3.

There are a number of critical parameters in the forming of the coat of substance on the surface 3. There is a minimum legal distance which any locomo' tive-mounted equipment must be maintained above the surface 3. Given this requirement, the temperature of the molten substance as it leaves the spraying apparatus and the distance of the spraying apparatus in front of the wheel 2 must be adjusted so that the substance is molten as it reaches the surface 3 but is able to cool and completely solidify before being reached by the wheel 2. The temperature can be adjusted directly by means of the heating coils 42 in apparatus 7 and indirectly by means of the gas mixture, voltage and current used in the plasma torch 10 of apparatus 6. In addition, the velocity at which the gas-substance mixture is delivered to the surface 3 must be low enough that most of the substance adheres to the surface 3 without splashing off, but must be high enough to avoid being blown off target by cross winds and missing the surface 3. This can be controlled by the pressure in the gas supply 44 of the apparatus 7; the velocity in apparatus 6 is controlled by conditions in the plasma torch 10 as well as the pressure of the gas in gas supply 20.

In tests with a nitrogen-hydrogen plasma torch using powdered sand, glass and slag, all substances were suc cessfully deposited on a section of railroad rail. The substances were pulverized and screened for mesh to produce particle sizes between 44 and 88 microns and 35 mesh to produce particle sizes between 250 and 500 microns. Slag was the easiest substance to deposit. The 170 mesh slag formed a satisfactory coat when sprayed from 4 inches; and the 35 mesh slag formed a coat sprayed from one inch. Both sand and glass formed good coats at 170 mesh and 1 inch.

Since further embodiments of our invention will occur to those skilled in the art, the invention should be limited only by the following claims.

It is claimed:

1. A process for improving the traction of a locomotive wheel on a railroad rail which comprises:

heating to the molten state a substance which be comes solid, friable and abrasive upon contact with the railroad rail,

depositing a coat of the substance on the wheelcontacting surface of the railroad rail ahead of the locomotive wheel, whereupon the coat of the substance solidifies,

and crushing the solidified coat of the substance under the locomotive wheel, whereupon the rail is scoured and traction is improved by the crushed substance.

2. The process of claim 1 wherein the substance is chosen from the group consisting of sand, glass and slag.

3. A process for improving the traction of a locomotive wheel on the wheel-contacting surface of a railroad rail which comprises:

storing in powder form a substance chosen from the group consisting of sand, glass and slag; feeding the substance to a plasma torch positioned adjacent the rail ahead of the wheel, whereupon the substance is heated to a molten state and deposited on the wheel-contacting surface to form thereon a coat of solidified substance; and

crushing said coat of solidified substance between the wheel and the wheel-contacting surface, whereby the wheel-contacting surface is scoured and the traction between the wheel and wheel-contacting surface is improved.

4. A process for improving the traction between a locontacting surface; Comotlve Wheel and the wheelcontactmg Surface of a and crushing the coat of solidified substance between railroad rail which comprises:

the wheel and the wheel-contacting surface, Stormg a molten Substance chosen from the group whereb the wheel-contactin surface is scoured consisting of sand, glass and slag; 5 y g Spraying the molten Substance with pressurized gas and thetraction between the wheel and the wheelonto the wheel-contacting surface, whereupon a Contactmg Surface lmprovfidcoat of solidified substance forms on the wheel- 

1. A PROCESS FOR IMPROVING THE TRACTION OF A LOCOMOTIVE WHEEL ON A RAILROAD RAIL WHICH COMPRISES: HEATING TO THE MOLTEN STATE A SUBSTANCE WHICH BECOMES SOLID, FRIABLE AND ABRASIVE UPON CONTACT WITH THE RAILROAD RAIL, DEPOSITING A COAT OF THE SUBSTANCE ON THE WHEEL-CONTACTING SURFACE OF SAID RAILROAD RAIL AHEAD OF THE LOCOMOTIVE WHEEL, WHEREUPON THE COAT OF THE SUBSTANCE SOLIDIFIES, AND CRUSHING THE SOLIDIED COAT OF THE SUBSTANCE UNDER THE
 2. The process of claim 1 wherein the substance is chosen from the group consisting of sand, glass and slag.
 3. A process for improving the traction of a locomotive wheel on the wheel-contacting surface of a railroad rail which comprises: storing in powder form a substance chosen from the group consisting of sand, glass and slag; feeding the substance to a plasma torch positioned adjacent the rail ahead of the wheel, whereupon the substance is heated to a molten state and deposited on the wheel-contacting surface to form thereon a coat of solidified substance; and crushing said coat of solidified substance between the wheel and the wheel-contacting surface, whereby the wheel-contacting surface is scoured and the traction between the wheel and wheel-contacting surface is improved.
 4. A process for improving the traction between a locomotive wheel and the wheel-contacting surface of a railroad rail which comprises: storing a molten substance chosen from the group consisting of sand, glass and slag; spraying the molten substance with pressurized gas onto the wheel-contacting surface, whereupon a coat of solidified substance forms on the wheel-contacting surface; and crushing the coat of solidified substance between the wheel and the wheel-contacting surface, whereby the wheel-contacting surface is scoured and the traction between the wheel and the wheel-contacting surface is improved. 